Ibn Daqiq al-'Id (1228-1302), is accounted as one of Islam's great scholars in the fundamentals of Islamic law and belief, and was an authority in the Shafi'i legal school.
Although Ibn Daqiq al-'Id studied Shafi'i jurisprudence under Ibn 'Abd al-Salam, he was also proficient in Maliki fiqh.
He served as chief qadi of the Shafi'i school in Egypt.
Ibn Daqiq al-'Id taught hadith to al-Dhahabi, al-Nuwayri, and other leading scholars of the next generation.
In his lifetime, Ibn-Daqiq wrote many books but his commentary on the Nawawi Forty Hadiths has become his most popular.
In it he comments on the forty hadiths compiled by Yahya Al-Nawawi and known as the al-Nawawi's Forty Hadith.
His commentary has become so popular that it is virtually impossible for any scholar to write a serious book about the forty hadiths without quoting Ibn-Daqiq.